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1.
It is known that tobacco leaves may contain 210Pb and 210Po in significant concentrations. The cumulative alpha-radiation dose due to the radioactive content of inhaled cigarette smoke and the increasing number of lung cancer cases explain the importance of the investigation. The present study investigated the activity concentrations of these two radionuclides in 29 Hungarian cigarette samples. The relation between 210Po/210Pb activity and nicotine/tar content of these cigarettes was also examined. 210Po was determined by alpha spectrometry using a PIPS detector after chemical leaching and spontaneous deposition of 210Po on a high nickel-content (25%) stainless steel disk. The 210Pb activity was calculated from the 210Po originated from the decay of 210Pb after a waiting period of eight months. The 210Po activity concentrations of the measured types of cigarettes ranged from 10.0 to 33.5 mBq/cigarette, and the activity of 210Pb varied from 9.6 to 32.5 mBq/cigarette. The average annual committed effective dose is estimated to be and due to cigarette smoking (20 cigarettes/day) for 210Po and 210Pb, respectively. 相似文献
2.
《Journal of Magnetic Resonance (1969)》1976,21(2):321-330
Electron spin resonance spectra of spin-trapped free radicals from tobacco smoke have been examined. The cigarettes studied were standard IRI research cigarettes supplied by the University of Kentucky Tobacco and Health Research Institute. Substantial changes in the spectra were observed upon aging of the samples. Aging for several days resulted in at least two remaining long-lived spin-adducts. For the experimental configuration employed the efficiency of the spin-trapping apparatus was determined to be about 47%. Utilizing measurement of the broadening of the magnetic resonance lines as function of the amount of smoke passed through the phenyl-t-butyl nitrone spin-trapping solution, a concentration of about 1 × 1018 free radicals per cigarette puff was deduced. The method employed in this determination was tested with a number of stable free radicals in several solvents. 相似文献
3.
R. T. Saito I. I. L. Cunha R. C. L. Figueira M. G. Tessler 《Czechoslovak Journal of Physics》2003,53(1):A75-A81
The purpose of this work was to determine levels of 210Pb and 210Po in seawater, sediment cores, fish and seafood as well as to estimate the concentration factors and the bioindicators for 210Pb and 210Po in marine organisms collected in the estuary. 210Pb levels in seawater varied from 2.1 to 6.2 mBq.L?1 and for 210Po ranged from 1.6 to 4.1 mBq.L?1. 210Pb concentration factors in fish varied from 0.5×102 to 0.8×103, in crustaceans from 0.5×103 to 0.2×104 and in shellfish from 0.2×104 to 0.3×104. 210Po concentration factors in fish varied from 0.9×102 to 0.5×104, in crustaceans from 0.5×104 to 0.2×105 and in shellfish from 0.3×105 to 0.9×105. The results obtained to the concentration factors indicated that shellfish and crustaceans are good bioindicators for the radionuclides studies. Some species of fish also accumulated significantly quantities of these radionuclides. 相似文献
4.
《Radiation measurements》2009,44(3):311-324
The huge Guarani aquifer located in the South American continent is a very important resource for the region, and its drinking water quality has been investigated according to international standards, inclusive radiological parameters. This paper describes 210Po and 210Pb activity concentration data in groundwater samples collected at the Brazilian portion of Guarani aquifer, that is characterized by a great variability of temperature (18–70 °C), pH (4.0–9.9), sodium content (0.3–322 mg/l), bicarbonate content (0.1–318 mg/l), etc. Non-expensive alpha counting following some radiochemical steps for extracting and depositing dissolved 210Po was used. The results of the measurements for samples collected in duplicate yielded a maximum 210Po activity concentration of 3.7 mBq/L and a maximum 210Pb activity concentration of 6.7 mBq/l, that are values greatly lower than the guidance level of 0.1 Bq/l established by the WHO for their presence in drinking water. The high sensitivity of the method allowed its applicability on the identification of complexes geochemical and hydrogeological processes occurring in Guarani aquifer as well on the evaluation of the drinking water quality in terms of dose calculations. 相似文献
5.
In this work, arsenic species in mainstream cigarette smoke condensates was systemically studied with inductively coupled plasma mass spectrometry. A single particle inductively coupled plasma mass spectrometry was utilized for analysis of the physical forms of arsenic, and no particle arsenic was observed in mainstream cigarette smoke condensates. The solvent extraction experiments proved that the water-soluble arsenic was the main species in mainstream cigarette smoke condensates, which was consistent with the result of single particle inductively coupled plasma mass spectrometry. Furthermore, speciation of arsenite, arsenate, monomethylarsonic acid, and dimethylarsinic acid was investigated using high performance weak anion exchange chromatography coupled with inductively coupled plasma mass spectrometry detection. The developed high performance liquid chromatography coupled inductively coupled plasma mass spectrometry method was successfully applied to the determination of arsenic species in mainstream cigarette smoke condensates with satisfactory recoveries. Four arsenic species were detected in the mainstream cigarette smoke condensates from four brands of commercial available cigarettes, and there was a great difference between the arsenic content and composition among the different brands of cigarettes. It is found that arsenate was the main species in all tested cigarette samples. 相似文献
6.
A method for the determination of Pb isotope ratios (IR) in cigarette tobacco by quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS) has been developed and applied to tobacco samples from genuine and counterfeit cigarettes obtained in the USA. The IR 207Pb/206Pb, 208Pb/206Pb, 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb were measured using a Q-ICP-MS instrument. Two certified reference materials, grown in the USA and Bulgaria, were also analysed for comparison with the tobacco samples, as were tobacco samples from cigarettes obtained in Pakistan and China. The precision of the results was sufficient to distinguish between the counterfeit and genuine USA cigarettes. All of the genuine cigarettes and both reference materials, grown in different regions, were statistically distinct based on the measured ratios. The counterfeit cigarettes were indistinguishable from the reference material grown in Bulgaria. The technique shows promise as a method for identifying counterfeit cigarettes, possibly determining the source region. 相似文献
7.
利用差分光学吸收光谱(DOAS)仪对不同品牌卷烟主流烟气中的NO2进行连续、实时、在线测量,使用RM200型转盘式20孔道吸烟机,一次将20只卷烟顺序输送到吸烟转盘上,间隔3 S依次点火,并将卷烟烟气通入与之直接相连的总光程为31.5 m的怀特池,利用差分光学吸收光谱技术,町在6~7 min之内完成对整只卷烟的逐口测量.提高了测量结果的时间分辨率.抽吸开始时,怀特池气压被抽到5.2×104Pa,所有卷烟完成测量时,气压恢复到1.03×105Pa;抽吸结束后,怀特池中NO2的浓度在0.89 mg/m3和1.54 mg/m3之间.比较不同品牌的卷烟,主流烟气中NO2浓度有明显差别,特别是混和型卷烟比烤烟型高83%,该技术对卷烟烟气成分的快速检测提供了,一种简便的方法. 相似文献
8.
The main aim of the present study was to evaluate 210Pb and 210Po emissions from the ?o?tanj TPP and to evaluate their mass balance in unit 4. Samples of coal, fly ash, slag and flue gases were analysed for 210Pb and 210Po content. The results showed that these radionuclides are mostly concentrated in ash (71% and 81% for 210Pb and 210Po, respectively). Only a small part of the input activity was detected in flue gases. The activities of 210Pb and 210Po in unit 4 were from 1.1 to 2.7 Bq m?3 and from 0.37 to 0.56 Bq m?3, respectively. The mass balance of the two radionuclides in unit 4 show only 6 and 10% differences between the annual activities of the input and output samples. 相似文献
9.
高效液相色谱测定卷烟及其主流烟气中的维生素E 总被引:1,自引:0,他引:1
样品用饱和抗坏血酸乙醇溶液萃取,ZORBAX Extend-C18(5μm,4.6×150mm)色谱柱及FLD检测器在激发波长为298nm,发射波长为325nm下检测,流动相为100%甲醇。采用外标法定量,线性相关系数为0.99996,检出限为0.12μg/mL,卷烟及其主流烟气中维生素E平均回收率分别为97.0%和97.4%,RSD分别为0.70%和4.70%。研究表明:烤烟型卷烟烟丝比混合型卷烟烟丝中维生素E含量高,烤烟型卷烟主流烟气比混合型卷烟主流烟气中维生素E含量高,维生素E从卷烟烟丝到主流烟气的迁移率为7%—16%。 相似文献
10.
Alicja Boryło Marcin Kaczor Bogdan Skwarzec 《Isotopes in environmental and health studies》2019,55(3):308-316
Herbs are an important part of traditional medicine in Poland. Therefore, the aim of this study was the determination of polonium 210Po in 48 selected medicinal herb samples from the Polish market. The activity concentrations of 210Po were measured using alpha spectrometry. The activity concentration of 210Po was in the range from 0.3?±?0.1 to 28.2?±?0.4 Bq kg–1. The obtained results were compared with corresponding studies conducted worldwide. A higher 210Po activity concentration was observed in the above-ground part of plants. The obtained results show that the highest 210Po activity concentration was observed in evergreen plants and winter-hardy plants. Yet even infusions with 2 g of the most contaminated herbs examined were considered to be radiologically safe. 相似文献
11.
T.S. Bhatia T.R. Canada P.D. Barnes R.A. Eisenstein C. Ellegaard 《Nuclear Physics A》1979,314(1):101-114
Energy levels of 209Po have been populated with the 210Po(d, t)209Po and 210Po(p, d)209Po reactions at bombarding energies of 17.0 and 17.8 MeV respectively. Fifteen levels were observed below 2.7 MeV of excitation. Energy levels of 211Po were populated with the 210Po(d, p)211Po reaction, also at 17.0 MeV. Thirty-five levels, almost all new, were observed below 3.9 MeV of excitation. Comparison of experimental angular distributions with DWBA calculations allowed l-value assignments and extraction of spectroscopic factors for many levels. In 209Po the observed level structure is well described in terms of a simple particle-vibration coupling model. In 211Po the level structure is more complex and the simple model is not adequate. 相似文献
12.
D. Pérez Sánchez A. Martin Sánchez M. Jurado Vargas 《Czechoslovak Journal of Physics》2003,53(1):A25-A30
A simple radiochemical procedure has been developed to determine 210Pb and 210Po in environmental samples from the same matrix. Sediment samples are decomposed by leaching with mineral acids or by microwave digestion, while water samples are pre-concentrated. One part of the resulting solution, spiked with 209Po, is used for 210Po determination by spontaneous deposition onto nickel disks (α-spectrometry). The other part is assayed for 210Pb, separating the Pb either by anion-exchange (sediment samples), or by solvent extraction (water samples). The 210Pb source is finally prepared by precipitation as oxalate and the chemical recovery determined by gravimetry. The 210Pb activity concentration is determined by liquid scintillation. A standard sediment sample supplied by IAEA and spiked water samples were analysed to check the procedure. The 210Pb and 210Po measurements agreed well with the certifications, deviations being less than 10%. The mean recoveries for Pb and Po were (70±12)% and (77±8%) for sediments, and (70±10)% and (81±7)% for waters, respectively. 相似文献
13.
The 209Bi(α,t)210Po reaction at 45 MeV has been used to study 210Po. Many new levels have been observed and proton configurations are suggested for the lowest three multiplets. 相似文献
14.
为了快速、 精确地从卷烟燃烧的主流烟气中求出氨的浓度信息,设计了基于红外吸收的检测系统。根据氨在中红外的特征吸收曲线,系统通过10.4 μm中红外固定波长激光器对准最强吸收峰波长位置。由红外探测阵列获取经被测主流烟气红外光的干涉条纹后,结合光谱数据库及光谱分析算法,由比尔朗伯定律求解主流烟气中的氨浓度。标准光谱数据选自NIST光谱数据库,结合对主流烟气中多种干扰气体的降噪处理,最终完成氨浓度信息的实时显示。实验采用UnicornTM固定波长激光器、 静态傅里叶变换干涉具、 标准抽吸引擎等,对五个不同品牌的卷烟进行测试。每个品牌随机抽取十支,分别采用传统的离子色谱法和本系统进行实验。结果显示,本系统的氨浓度检测与标准值基本一致,同时速度快、 抗干扰能力强。 相似文献
15.
Joga Singh Harmanjit Singh Surinder Singh B. S. Bajwa 《Indian Journal of Physics》2009,83(8):1147-1153
Radium concentration and radon exhalation rate have been measured in soil samples collected from some areas belonging to upper
Siwaliks of Kala Amb, Nahan and Morni Hills of Haryana and Himachal Pradesh states, India using LR-115 type II plastic track
detectors. Uranium concentration has also been determined in these soil samples using fission track registration technique.
Radium concentration has been found to vary from 5.30 to 31.71 Bq.kg−1, whereas uranium concentration varies from 33.21 to 76.26 Bq.kg−1. The radon exhalation rate in these samples varies from 216.87 to 1298.00 mBq.m−2hr−1 (6.15 to 36.80 mBq.kg−1.hr−1). Most of the samples have uranium concentration above the worldwide average concentration of 35 Bq.kg−1. A good correlation (R
2 = 0.76) has been observed between uranium concentration and radon exhalation rate in soil. The values of uranium, radium
and radon exhalation rate in soil are compared with that from the adjoining areas of Punjab. 相似文献
16.
卷烟主流烟气是卷烟燃烧时被人体吸食到体内的主要气体,其减焦降害已成为全社会高度关注的问题。在各种卷烟主流烟气组分中,巴豆醛以其强烈的基因毒性,成为国家规定的卷烟中七种主要有害指标物之一。传统的巴豆醛分析方法大都采用高效液相色谱法等实验室分析方法,需繁琐的样品前处理过程,无法测量巴豆醛的实时浓度,难以准确评估巴豆醛对人体健康的影响。为了快速、准确地检测卷烟主流烟气中的巴豆醛组分,本研究搭建了一套可以直接与吸烟机耦合的傅里叶红外光谱分析系统(FTIR),并创新性开发过采样数据驱动光谱分析方法(ODDSA),从复杂、变动的卷烟主流烟气中准确提取巴豆醛的光谱组分信息。ODDSA方法从实验设计入手,采用随机设计的思路尽可能模拟实际卷烟样品的分布范围,以构建具备良好光谱数据结构的样品集。在此基础上,创新性地将高密度小波变换引入红外光谱数据的处理过程中,以时/频双域过采样的方式提升了光谱解析分辨率,进而降低了其他基质组分对巴豆醛光谱信息的干扰。最后,发展改良竞争自适应重加权采样方法,从多倍冗余的高密度小波系数中准确提取待测物质的最佳变量组合,由此构建高质量的巴豆醛光谱定量分析模型。为了验证ODDSA方法的有效性,实验中采集了15种典型市售卷烟品牌,每个品牌在线采集8支样品的主流烟气红外光谱,随后采用随机挑选的25个验证集样本对ODDSA方法进行验证。结果表明,检验集的线性拟合系数为0.971,相对均方根误差为5.5%,其预测精度能有效满足卷烟主流烟气中巴豆醛的在线分析需求,并可拓展到环境二手烟气中其他组分的在线监测,进而为吸烟与健康评估提供全新手段。 相似文献
17.
H. Klein I. Wiedenhöver H. Tiesler H. Meise A. Fitzler A. Dewald H.G. Thomas D. Weißhaar P. von Brentano 《The European Physical Journal A - Hadrons and Nuclei》1999,4(3):221-223
An in-beam experiment with the subcoulomb reaction 209Bi(3He, d*γγ)210Po at 20.5 MeV was performed with two Euroball Cluster detectors in Cologne. It closed the gap between the low energy levels
of the level-scheme and the high energy levels found in 209Bi(3He, d)210Po and 208Pb(4He, t)210Po particle experiments. New branchings have been found and the (3He, d*γγ) reaction below the coulomb-barrier has been used successfully.
Received: 17 December 1998 / Revised version: 27 January 1999 相似文献
18.
238U and 232Th concentrations as well as 222Rn and 220Rn α-activities per unit volume were measured in various natural honey samples collected from different regions in Morocco using
CR-39 and LR-115 type II solid state nuclear track detectors (SSNTDs). These radionuclides were also measured in soils, plant
flowers and nectar solutions corresponding to the honey samples studied. In addition, these radionuclides were measured in
different imported honey samples. The measured 238U, 232Th, 222Rn and 220Rn concentrations ranged from (1.5±0.1) mBq kg−1 to (10.6±0.6) mBq kg−1, (1.1±0.1) mBq kg−1 to (4.2±0.2) mBq kg−1, (1.5±0.1) Bq kg−1 to (10.6±0.6) Bq kg−1 and (1.1±0.1) Bq kg−1 to (4.2±0.2) Bq kg−1 for the honey samples studied, respectively. Annual 238U, 232Th and 222Rn intakes by Moroccan adults from the consumption of honey were assessed. The influence of the nature of soil and plant on
the 238U and 232Th contents of the studied honey samples was investigated. These measurements were completed by an investigation of the 238U and 232Th transfer between soils and plant flowers and that between plant flowers and honey, and also by the investigation of the
influence of pollution due to different material dusts on 238U, 232Th and 222Rn in the honey samples studied. Committed equivalent doses due to the annual intake of 238U, 232Th and 222Rn were evaluated in the organs of adult members of the Moroccan rural population from the ingestion of the honey samples.
The maximum total committed effective dose due to 238U, 232Th and 222Rn from the ingestion of natural honey by the Moroccan rural population was found to be equal to 0.64 μ Sv y−1. 相似文献
19.
不具有荧光的探针双氢罗丹明6G被氧化后可以生成具有荧光特性的罗丹明6G。反应中,一个双氢罗丹明分子能够与2个活性氧发生作用。借助衍生荧光检测技术,可以将该探针用于香烟主流烟雾活性氧含量的检测实验。利用探针在该实验条件下检测市场上4种品牌香烟的主流烟雾中活性氧的含量,含量分别为:(59.93±5.32)nmol,(55.98±6.17)nmol,(54.78±7.82)nmol,(40.87±6.43)nmol。实验结果表明,香烟主流烟雾中活性氧的含量与烟草品种及制作工艺存在密切的联系。借助荧光特性进行主流烟雾活性氧含量近实时检测的方法具有灵敏度高与检测速度快的特点。 相似文献
20.
A possible way to remove the discrepancy between calculated and measured α-widths is discussed. The decay rates of 212Po and 210Po are computed with the help of shell-model wave functions for parent and daughter nucleus. 相似文献